I have a 73 F100 with 360 2bbl and a C6 A/T. The column shifter does not really lock into gear (I think the detents are gone). When driving, if I punch the gas it will shift gears on me usually drop into second. and by this I mean the column shift lever will move. I have checked the engine mounts and they are in one piece, so engine movement could not be causing the shifting. I am wondering if moving to a floor mounted cable shifter should cure the problem, or is the problem in the tranny itself. I have a shifter already from a donor truck (Black Ice + Tree = donor truck) any help would be appreciated.

Scott in Washington State

 

I would disconnect the shift linkage from the trans & make sure the shift lever stops frimly in each the gear.

 

With the linkage disconnected, it does take a little pressure but not much to shift. it seems to click into gear but not really snug. kind of a weak click.

 

I've never seen a detent roller go bad but, that is what holds it in a gear.

 

Where is the detent roller located. in the transmission? Easily accessible? Or should I pay someone knowledgeable to look at it? I am very handy, but I cannot really find a blowup of the tranny.

 

Might as well service your tranny. Get the fluid and filter/gasket kit and when you get the pan off the tranny you will be able to see the shift lever detent pretty easy. With the linkage disconnected you will be able to see the function of the system while you move the lever on the side of the tranny by hand. Then you can better evaluate what the situation is.

 

Its in the trans. above the valve body. You can see it up in there if you remove the pan. I would try taking it for a ride after disconnecting the linkage from the trans & see if it slips out of drive before tearing it apart.
There is a stop built into the column shifter at drive. You should have to pull the shifter back to get into second & first.

 

could be a broken motor mount, when you hit the gas the motor and tranny twists away from the rest of the truck and the linkage pulls it into another gear, dad had a buick that did that

 

Scott says the mounts aren't broken.

 

Scott states that the engine mounts are good but what about the trans mount?